So in the process of rebuilding my 2 X3V's and trimming/tracking them, I get to thinking... Why is the default curve on these birds
Idle up: 35-45-55-60-65
Normal: 45-50-55-60-65

On both my X3V's this ptich curve pushes the 0 pitch to below mid stick, what is the reason for not have 0 pitch at mid stick? Also... in idle up mode, why is the pitch curve not the same on either side of the middle point, It flattens out on the top half? I'm sure there's a reason for it. But what?

So in the process of rebuilding my 2 X3V's and trimming/tracking them, I get to thinking... Why is the default curve on these birds
Idle up: 35-45-55-60-65
Normal: 45-50-55-60-65

On both my X3V's this ptich curve pushes the 0 pitch to below mid stick, what is the reason for not have 0 pitch at mid stick? Also... in idle up mode, why is the pitch curve not the same on either side of the middle point, It flattens out on the top half? I'm sure there's a reason for it. But what?

Just wondering? Anybody?

MG

Those are the correct default settings.
Adjust the pushrods so that the pitch is zero at mid stick; ensure that the main shaft is not floating up or down and is clamped down well with the top collar; ensure that the main shaft bottom is not protruding below the edge of the outside, bottom of the main gear spindle

Those are the correct default settings.
Adjust the pushrods so that the pitch is zero at mid stick; ensure that the main shaft is not floating up or down and is clamped down well with the top collar; ensure that the main shaft bottom is not protruding below the edge of the outside, bottom of the main gear spindle

Those are the correct default settings.
Adjust the pushrods so that the pitch is zero at mid stick; ensure that the main shaft is not floating up or down and is clamped down well with the top collar; ensure that the main shaft bottom is not protruding below the edge of the outside, bottom of the main gear spindle

So I gave it a go, but for the life me I couldn't get is so that the -ve / +ve pitch in idle up mode matched when forcing mid stick to be 0 pitch. I've noticed that the travel of the servos from mid stick to full +ve pitch is greater than the travel from mid stick to full -ve pitch... it's this way on both my X3V's and this being the case, wouldn't it mean that it's effectively impossible for mid stick to be 0 pitch?

So I gave it a go, but for the life me I couldn't get is so that the -ve / +ve pitch in idle up mode matched when forcing mid stick to be 0 pitch. I've noticed that the travel of the servos from mid stick to full +ve pitch is greater than the travel from mid stick to full -ve pitch... it's this way on both my X3V's and this being the case, wouldn't it mean that it's effectively impossible for mid stick to be 0 pitch?

Yeah I gave that a go as well trying to find a position for the servo horns so that I could get 0 pitch at mid stick and equal +ve/-ve pitch either side while using the default pitch curve, but just couldn't do it...

Quote:

Originally Posted by MightyG

... why is the pitch curve not the same on either side of the middle point, It flattens out on the top half? I'm sure there's a reason for it. But what?
MG

But as per my first post why is the pitch curve the way it is?
Here's a graph of the default idle up/nomal pitch curve on in the X3V TX

From what I've read here about pitch curves... on a 5 point curve mid stick is at 3 so shouldn't the pitch value be 50% at point 3?
From the current curve the pitch value of 50% would place mid stick at point 2.5... Either side of 50% the delta of the pitch values at point 1 & 5 are the same (15%) so that's ok...

You can also see that the pitch curve for the WNCP(X), doesn't have point 3 at 50% either, but when using the tx the stick is much closer to mid stick for pitch 0 (I assume it has something to do with the geometry) than when flying the X3V. As you can also see, the curve is the same either side of point 3.

Cheers

MG

Images

Arrrrhhhh, tried to get it all going by slowly tweeking the servo horns, servo rods & pitch rods, and I just could not for the life of me get mid stick = 0 AND for the +ve and -ve pitch to be the same in idle up mode...

So I said stuff it... and reset the entire pitch curve so that mid stick = 50%. 15min later all is done and I've out the back yard testing the new setup to tweek and track the blades... So here's my new pitch curve.. +/- 11 degrees either side of mid stick and mid stick = 0 pitch. Pretty much straight with a slight tweak around the mid stick region to increase the aggressiveness of the collective there (well, 1% more aggressive!). As I get more experience I'm sure I'll be changing it! When I get a nice day I'll take her to the park and try flipping & holding her inverted.... fingers crossed!

Images

Arrrrhhhh, tried to get it all going by slowly tweeking the servo horns, servo rods & pitch rods, and I just could not for the life of me get mid stick = 0 AND for the +ve and -ve pitch to be the same in idle up mode...

So I said stuff it... and reset the entire pitch curve so that mid stick = 50%. 15min later all is done and I've out the back yard testing the new setup to tweek and track the blades... So here's my new pitch curve.. +/- 11 degrees either side of mid stick and mid stick = 0 pitch. Pretty much straight with a slight tweak around the mid stick region to increase the aggressiveness of the collective there (well, 1% more aggressive!). As I get more experience I'm sure I'll be changing it! When I get a nice day I'll take her to the park and try flipping & holding her inverted.... fingers crossed!

My heli has out the box the zero pitch at 50% but due the pitch curve it is not at mid stick. This is actually a no sense and the only reason i can think of is that they made that way for make it more beginner friendly. It is pretty easy to take off but i don't like it very much. I'll try your pitch curve and i'll probably increase throttle curve close to zero pitch because in order to have a soft landing.

My heli has out the box the zero pitch at 50% but due the pitch curve it is not at mid stick. This is actually a no sense and the only reason i can think of is that they made that way for make it more beginner friendly. It is pretty easy to take off but i don't like it very much. I'll try your pitch curve and i'll probably increase throttle curve close to zero pitch because in order to have a soft landing.

The factory settings are the most effective for most pilots.
Maybe reduce the throttle curve to 35% at first setting to help with more gentle landing.
YOU can adjust them if you like - however lower values at the low end of the stick will produce less lift - higher values at upper end of the stick will produce MORE lift BUT at the cost of more battery usage and stress on motor. Should you need to go back to factory settings here are the recommended settings: